Mechanisms of Enhanced Arbovirus Infection by Mosquito Saliva

描述（由申请人提供）：节肢动物传播的病毒（虫媒病毒）是造成世界范围内重大疾病负担的原因。在这里，我们将研究蚊子-病毒-宿主相互作用-一个重要的研究领域，所有蚊媒病毒。蚊子唾液可以增强几种不同虫媒病毒的病毒复制，这取决于蚊子种类、病毒和实验系统；然而，增强病毒复制的机制尚不清楚。研究这些机制和确定负责的唾液因素是本建议的目标。我们的研究模型将是西尼罗河病毒（WNV），其地方性媒介之一，库蚊tarsalis，和小鼠作为脊椎动物宿主。我们之前的研究表明，蚊子唾液增强了该模型中的早期病毒复制。我们将在这些研究的基础上追求三个相关的目标：1)确定蚊子唾液如何影响病毒的产生。由于更多的病毒产生是由于更多的细胞被感染和/或每个细胞的产量更高，我们将在这些研究中探索这两种可能性。2)使用系统生物学方法检测蚊子唾液存在时宿主对西尼罗河病毒的反应。由于增强的病毒复制发生在感染后的早期，我们假设蚊子唾液抑制了先天免疫反应。我们将使用微阵列研究来检测在有和没有蚊子唾液的西尼罗河病毒感染期间靶组织中表达谱的差异。3)确定蚊子唾液成分对西尼罗河病毒感染的增强负责。我们的初步研究已经将可能的候选蛋白缩小到在库蚊和埃及伊蚊中发现的两个蛋白家族，但在冈比亚按蚊中没有发现。我们将确定这些候选物中哪一个负责病毒增强，随后将其作为可能的疫苗进行测试。在完成这些目标后，我们将对了解虫媒病毒在蚊子传播背景下的发病机制做出重大贡献，并为开发减少病毒传播的新靶点奠定基础。

DESCRIPTION (provided by applicant): Arthropod-borne viruses (arbovirus) are responsible for a significant disease burden worldwide. Here, we will investigate the mosquito-virus-host interaction - an important area of research for all mosquito- borne viruses. Mosquito saliva potentiates viral replication for several different arboviruses, depending on the mosquito species, virus and experimental system; however, the mechanism(s) of enhanced viral replication is not well understood. Investigating these mechanism(s) and identifying the responsible salivary factors are the objectives of this proposal. Our model for these studies will be West Nile virus (WNV), one of its enzootic vectors, Culex tarsalis, and mice as the vertebrate host. Our previous studies showed that mosquito saliva enhances early viral replication in this model. We will build on these studies by pursuing three related aims: 1) Determine how mosquito saliva affects viral production. Since greater viral production is due to either greater numbers of cells infected and/or greater yield per cell, we will explore both possibilities in thes studies. 2) Use a systems biology approach to examine the host response to WNV in the presence of mosquito saliva. Since the enhanced viral replication occurs early after infection, we hypothesize that the innate immune response is inhibited by mosquito saliva. We will use microarray studies to examine differences in expression profiles in target tissues during WNV infection with and without mosquito saliva. 3) Identify the mosquito salivary component(s) responsible for enhancement of WNV infection. Our preliminary studies have narrowed the possible candidates to two protein families found in Culex tarsalis and Aedes aegypti, but not in Anopheles gambiae. We will determine which of these candidates is responsible for viral enhancement and subsequently test it as a possible vaccine. Upon the completion of these aims, we will have made significant contributions to understanding arbovirus pathogenesis in the context of mosquito transmission and laid the groundwork for the development of novel targets to reduce viral transmission.